Ass backwards is a colloquial term that refers to doing something in an illogical or backwards way. Although it's a commonly used phrase, there are a variety of synonyms that can be used in place of it. These synonyms include a**-up, backwards logic, inverted, reversed, topsy-turvy, contradicting oneself, and opposite. Some people might use other colorful phrases like 'bass ackwards', 'arse backwards', or 'bass ackward'. These synonyms can be used interchangeably depending on the context and the speaker's preference. Regardless of the word choice, it all describes the same thing: when someone approaches a situation in a completely irrational way.